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In the operation and maintenance system of urban underground pipe networks, the treatment of trenchless sewer sludge has always been an unavoidable pain point. This kind of sludge, a mixture of sediment, oil stains, domestic waste, and pipe deposits, not only has a water content often exceeding 80%

In the operation and maintenance system of urban underground pipe networks, the treatment of trenchless sewer sludge has always been an unavoidable pain point. This kind of sludge, a mixture of sediment, oil stains, domestic waste, and pipe deposits, not only has a water content often exceeding 80% and complex, variable components but also poses risks: random stacking can cause soil and groundwater pollution, while traditional landfill disposal faces the dilemmas of low reduction efficiency and nearly zero resource utilization rate—leaving many urban pipe network operation and maintenance units "headache-stricken". However, the trenchless sewer sludge treatment equipment developed by Desen Environment, with its core design of "on-site operation and full-process closed-loop", is becoming a key force in solving this problem.  

Step into any Desen trenchless sewer sludge treatment site, and the modular production line always catches the eye quickly—no need to build fixed workshops in advance; the equipment can complete assembly and commissioning within 2 hours after arriving at the site. Whether it is an open municipal site or a narrow corner of an industrial park, it can be flexibly adapted. After the transport plant pours the wet sludge into the feed inlet, the treatment process starts in an orderly manner:  

1. **Multi-stage screening for homogenization**: First, the high-efficiency screening module in the multi-stage screening system works. The coarse screen separates large impurities such as dead branches and plastic bags, while the fine screen filters out small sand particles. This makes the sludge to be treated achieve "homogenization", avoiding efficiency impacts caused by impurity clogging in subsequent links.  

2. **High-efficiency deep cone thickening**: The pretreated sludge then enters the high-efficiency deep cone thickening module. Based on the oil content, viscosity, and other characteristics of the sludge, the equipment automatically and accurately deploys a special chemical agent. Through stirring, the agent fully reacts with the sludge, quickly breaking the colloidal structure in the sludge, and completely "dissociating" the water and pollutants originally wrapped in the sludge particles—laying the foundation for deep dehydration.  

The deep dehydration link is the core of realizing sludge volume reduction. The conditioned sludge is transported to the high-pressure plate-and-frame filter press module. Under the action of specific pressure, the free water and bound water in the sludge are gradually squeezed out, and finally, dry sludge cakes with a stable moisture content of less than 60% are formed. On-site data shows that after treatment, 10 cubic meters of wet sludge can only produce about 3 cubic meters of dry sludge cakes, with a volume reduction rate of over 70%. This means that the subsequent transportation costs and disposal site requirements are significantly reduced.  

More notably, the polluted wastewater generated during the dehydration process flows directly into the integrated water treatment module built into the equipment. After treatment by the "coagulation sedimentation + membrane filtration" process, it not only meets the discharge standards but also part of the clean water can be recycled for equipment cleaning or chemical preparation—truly achieving no secondary pollution in the entire process.  

The treated dry sludge cakes are not "waste" as traditionally perceived. Tested by third-party testing institutions, indicators such as heavy metal content and organic matter content all comply with the standards of *Sludge Disposal from Municipal Wastewater Treatment Plants - Quality of Sludge for Landscaping* (GB/T 23486-2009). They can be directly used in scenarios such as park greening soil covering and municipal road subgrade backfilling, turning the original "polluted sludge" into recyclable resources and realizing the treatment goals of "harmlessness, reduction, and recycling" of trenchless sewer sludge.  

From the perspective of project practice, the strength of Desen trenchless sewer sludge treatment equipment has been verified in many places:  

- In an old pipe network renovation project in Jiangsu, the local trenchless sewer sludge had high oil content and viscosity due to long-term accumulation. Traditional equipment frequently encountered problems such as screen clogging and incomplete dehydration. By optimizing the screening gap and chemical formula in a targeted manner, Desen’s equipment not only achieved a daily sludge treatment capacity of 50 cubic meters but also stably controlled the moisture content of the sludge cake below 55%. The chemical oxygen demand (COD) of the wastewater was even reduced from the initial 3000mg/L to below 500mg/L, far exceeding the local environmental protection discharge standards.  

- In a dredging project of an industrial park in Guangdong, facing the requirements of narrow site and tight construction period, the equipment relied on the advantage of modular rapid deployment and completed the treatment of 200 cubic meters of trenchless sewer sludge within 15 days. Compared with the traditional landfill method, the cost was reduced by 40% and the cycle was shortened by nearly half, winning high recognition from the project party.  

For urban pipe network operation and maintenance units and environmental protection enterprises, the value of Desen trenchless sewer sludge treatment equipment lies not only in its advanced technology but also in its design that meets practical needs—modular layout adapts to complex sites, PLC intelligent control system reduces manual intervention, and full-process closed-loop treatment eliminates pollution transfer. With the continuous growth of China’s demand for urban pipe network dredging and maintenance, the standardized treatment of trenchless sewer sludge has become an important part of ecological and environmental protection construction. Desen Environment is using technology as a pen and equipment as a carrier to provide reliable support for "dredging and reducing the burden" of urban underground facilities and promoting the trenchless sewer sludge treatment industry to a new stage of higher efficiency, better environmental protection, and greater sustainability.